Pitman connection



Au .19,1941. a KELLER- 2,253,032

PITMAN CONNECTION Filed July 6, 1938 INVENTOR WITNESS ATTORNEYS PatentedAug. 19, 1941 UNiTED STATES PATENT OFFICE PITMAN CONNECTION Cleo D.Keller, Farrington, Wyo.

Application July 6, 1938, Serial No. 217,744

3 Claims.

My invention relates to pitman connections and more particularly to theconnection between the pitman sticks and the pitman boxes.

Ordinarily the pitman stick is connected to the pitman box by aplurality of transversely extending bolts equipped with washers andnuts. Due to the torque imparted to the assembled structure, aconsiderable number of bolts are ordinarily employed to effect theconnection between the box and stick and thus, due to the large numberof bolts, increases the weight of the assembly and consequently requiresa heavier fly-wheel and crank arm bushing.

It is therefore one of the principal objects of my invention to providea connection so arranged and constructed a to employ a minimum number ofbolts for connecting the stick to the box thereby enabling fiy-wheelsand bushings of a lesser weight to be employed with a resultant economyin manufacturing.

Another object of my invention is to provide a device of the abovedescribed character so constructed and arranged as to reduce frictionbetween the stick and box due to relative creeping when the pitman rodis being operated.

A further object of my invention is to provide a device of the abovedescribed character, which is simple in construction, durable in use,and efficient in operation.

Other objects and advantages will be apparent from the followingdescription, appended claims and annexed drawing.

Referring to the drawing wherein like reference characters designatelike parts throughout the several views:

Figure 1 is a perspective view of my invention illustrating the sameattached to the crank arm of a mowing machine.

Figure 2 is a side elevation of my invention.

Figures 3 and 4 are sectional views taken on the lines 3-3 and 4-4 ofFigure 2 respectively.

Figure 5 is a fragmentary side elevation of the pitman box.

In practicing my invention, for the purpose of illustrating the same, Iemploy a fly-wheel 5 of a mowing machine or the like equipped with theusual crank arm 6, the foregoing being of an ordinary or typicalconstruction. A pitman box; 1 is fashioned with a crank arm opening 8receiving said crank arm 6 for imparting reciprocation to said box andsaid arm is fashioned with a bushing 9 engaging the peripheral wall ofthe opening 8. The outer end of the pitman box '1 extends within a kerfIi) fashioned in the end of a pitman stick ll'as illustrated in thedrawing.

Said kerf 10 extends longitudinally and vertical and is fashioned onopposite opposed faces with registering pairs of semi-circular groovesl2 extending through the bottom face of the stick, the upper ends ofsaid grooves terminate subjacent the upper face of the stick. Formed inthe end of the box 1, which extends within the kerf lilare a pair ofspaced elongated slots l3 in registry with the grooves I2 and positionedin said slots [3 and extending into said grooves are a pair of elongatedfriction rollers M. The box 1 is provided with bolt receiving aperturesl5, one located on each side of the slots l3, and said apertures l5register with similar apertures extending through the stick I l. Bolts I6 extend through said apertures l5 and the registering apertures of thestick and are provided with lock Washers l1 and nuts l8 whereby tosecure the sides of the stick clamped to the end of the box locatedwithin the kerf I0. When the parts are thus assembled, the rollers serveto take up the torque between the box and stick caused by creeping andthus relieve wear on the bolts it. Also by the use of the rollers l3, alarge number of transversely extending bolts is eliminated, thuslessening the weight of the pitman assembly. By thus lessening theweight of the pitman assembly, a lesser weight fly-wheel and bushing maybe employed thus effecting an economy in manufacturing.

While I have shown and described my invention in connection with thefly-wheel of a mowing machine, it is to be distinctly understood that mydevice may be employed in other machine organizations without departingfrom the spirit of the invention or scope of the appended claims.

What I claim is:

1. In a device of the character described, a pitman member fashionedwith a section formed with spaced slots extending therethrough, a pitmanstick fashioned with a kerf having oppositely disposed spaced wallsprovided with grooves registering with said slots, and rollers mountedin said slots and extending into said grooves whereby to receive torquetransmitted from said member to said stick when said stick is secured tosaid member.

2. In a device of the character described, a pitman member fashionedwith a section formed with spaced slots extending therethrough, a pitmanstick fashioned with a kerf having oppositely disposed spaced wallsprovided with aligned grooves registering with said slots, rollersmounted in said slots and extending into said grooves whereby to receivetorque transmitted from said member closing said perforation, said wallsprovided with recesses registering with said perforation, and arotatable element mounted in said perforation and extending into saidrecesses to receive torque transmitted from said member to said stickwhen the latter is secured to said member.

CLEO D. KELLER.

